Circuit Description
WARNING: This page is about a different car, the 2004 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
The actual throttle position (TP) is compared to an expected throttle position based on engine load. The powertrain control module (PCM) determines engine load based on inputs from the mass air flow (MAF) sensor and the manifold absolute pressure (MAP) sensor. Further comparisons are done to distinguish if a sensor is at fault, and the respective DTC will set. If the PCM detects that the current load and throttle position are not consistent with the expected load and throttle position, DTC P0068 will set.